The United States shifted from military strikes to expanded economic sanctions against Iran as Oman-brokered discussions on a temporary Strait of Hormuz navigation corridor advanced and oil prices fell on the announcement [3][10]. Treasury Secretary Scott Bessent unveiled "Operation Economic Outcast," expanding secondary sanctions to five sectors — digital assets, technology, gold, aviation, and shipping — and targeting nearly 60 entities, while warning that any country conducting business with Iran risks exclusion from the dollar-based financial system [6][27]. President Donald Trump stated on Truth Social that all mines had been removed or detonated from the strait's international waters and warned that any vessel placing new mines would be destroyed [34][40].

Bessent framed the campaign as the "single greatest financial offensive ever" against Iran, presenting Tehran with a choice between "complete global isolation and a subsistence economy, or a path back to normalcy" [8][20]. He stated that Trump was making phone calls to world leaders demanding they cease interactions with Iran, and that every country had a defined timeline to shut down identified activities [27][31]. Bessent declined to name specific countries or deadlines, asking "Why would I want to blow up the global financial system?" and saying affected parties would be given a "cure period" to comply [12][19]. Israeli Prime Minister Benjamin Netanyahu thanked Trump for the sanctions, saying they "rightly exact a heavy price from the cruel dictatorship" [48]. US Defense Secretary Pete Hegseth maintained that kinetic strikes were not foreclosed, stating the US was "by no means foreclosing using kinetic strikes anywhere in the strait of Hormuz or around Iran" [16].

Iranian officials rejected the sanctions as a repetition of a failed strategy. Economy Minister Ali Madanizadeh stated Tehran was "fully prepared" with a two-year contingency plan and predicted "another defeat" for Washington [8][15]. Parliament Speaker Mohammad Bagher Ghalibaf said Iran's trading partners had communicated they did not take the US statements seriously [25][32]. Foreign Minister Abbas Araghchi dismissed the measures as "bound to fail," stating "We have seen this movie before. Same bull. Different bullies" [39].

Iranian and independent analysts called the sanctions an admission of military failure. Deputy Foreign Minister Kazem Gharibabadi asked "Is this a victory or an admission of America's defeat?" [15]. IRIS analyst Romuald Sciora described the announcement as "an admission of weakness," arguing months of bombing had failed and the Strait of Hormuz remained closed [24]. University of Tehran professor Hassan Ahmadian said there was "not a single new sanction" and the fanfare was "a public admission of a major step backward" after military failure [35]. Center for International Policy fellow Sina Toossi said Washington was "trying to accomplish through intensified economic strangulation what military force has so far failed to achieve" [16]. Center for American Progress senior fellow Andrew Miller said the war had brought the US "no closer to eliminating Iran's nuclear programme or crippling the Iranian regime" [16]. National Iranian American Council president Jamal Abdi called the measures "a retreat back to a strategy" Washington has pursued for years [32].

Iranian security officials threatened retaliation against any country joining the sanctions campaign. Supreme National Security Council Secretary General Mohsen Rezaei warned that if neighboring countries join the US economic war, "not a drop of oil will leave the Persian Gulf and the strait of Hormuz" [29][35]. Armed Forces Chief of Staff Ali Abdollahi said retaliation could take the form of land, sea, air, or cyber operations [16]. IRGC spokesperson Brigadier General Hossein Mohabbi warned of major strikes on US interests and energy supply routes if Iran's infrastructure was threatened [23][32]. Iranian foreign ministry spokesperson Esmaeil Baqaei said obliging countries to stop trade with Iran violated "the most fundamental pillar of the UN charter regarding national sovereignty" and would result in "the complete erosion of sovereignty" [35][39]. International lawyer Reza Nasri argued the sanctions were "not a measure against Iran" but "a claim of jurisdiction over the world" with "sovereignty itself" as the target [35].

Diplomatic mediation advanced on multiple tracks. Oman's Foreign Minister Badr al-Busaidi said he hoped Iran and Oman would "soon announce" a temporary joint navigation corridor through the Strait of Hormuz, with a permanent solution to follow [11][34]. Pakistan's army chief Asim Munir visited Tehran carrying a US message aimed at restarting the stalled political process, with Iranian officials describing the visit as "highly fruitful" [2][34][44]. Pakistan's Interior Minister Mohsin Naqvi said "significant progress" had been made in talks focused on de-escalation [11]. Qatar's foreign ministry spokesperson Majid Al-Ansari called the US sanctions "unilateral" and expressed support for mediation [1]. Russia's Deputy Foreign Minister Alexander Alimov said Moscow was ready to support mediation efforts if asked [47].

Oil prices dropped approximately 2% on hopes for progress in the Iran-Oman talks, with analyst Mitsuru Muraishi of Fujitomi Securities saying the market was reacting to developments surrounding Hormuz navigation and that hopes for progress had triggered selling [10]. The US began sending evacuated diplomatic personnel back to missions in the Middle East, signaling a perceived lower risk of near-term conflict [10][37].

China rejected the sanctions as illegal unilateral coercion. Foreign Ministry spokesperson Lin Jian stated China "firmly opposes illegal unilateral sanctions" and will "take all necessary measures to firmly safeguard its own rights and interests," calling the measures "economic war" that destabilizes the global financial order [11][24][28]. Peking University academic Wang Dong said it remained to be seen whether the US was "bluffing" and that China would defend its national interests "without hesitation" if targeted [18]. BBC Chinese reported that Bessent did not name China specifically, with analysts pointing to Xi Jinping's scheduled White House visit on September 24 as giving Trump reason to avoid confrontation with Beijing [46][31].

Independent economists questioned the sanctions' likely impact. Capital Economics chief climate and commodities economist David Oxley called the direct impact on Iran's energy revenues "somewhat of a damp squib" because the existing US naval blockade had already halted oil exports [8]. Iran's own Central Bank Governor Abdolnaser Hemmati admitted that crude exports had "virtually stopped" [35][42]. Center for a New American Security adjunct senior fellow Rachel Ziemba described the measures as "mostly incremental," aimed at intimidating remaining trading partners [3]. Georgetown University in Qatar professor Paul Musgrave said Trump was trying to "unilaterally assert the kind of coordinated sanctions that traditionally has taken multilateral coordination" [39].

Analysts and officials warned of collateral economic damage to third countries. Iraq, dependent on Iranian gas for electricity and holding over $10 billion in annual trade with Iran, was identified as among the most exposed [12][30]. Chatham House associate fellow Neil Quilliam said Iraq's vulnerability came less from the scale of its trade with Iran than from its dependence on continued access to the US-led financial architecture [12]. Federal Reserve Bank of Minneapolis president Neel Kashkari said the Middle East conflict was "now a big driver of what's happening on inflation" because energy prices affect every facet of the US economy [32]. Post Oak Group managing director John Deal warned that Americans could feel sanctions-driven retaliation through gasoline, diesel, airfares, freight costs, and inflation [3][32].

Tehran residents described immediate hardship. Shopkeeper Hussein Alizadeh reported a 45% drop in sales since the war began, calling the situation "psychological warfare" [13]. Administrative worker Ali said prices were increasingly high and "we feel poorer every day" [13]. Pharmacist Sarah Hassanbeigi said "I don't think people can really take this much longer" [15].

Gulf states faced divergent calculations. Lancaster University professor Simon Mabon said the UAE was "furious with Iran" after taking a beating during the conflict, while Saudi Arabia, Qatar, and Oman calculated that geography forced coexistence with Tehran [29]. Foundation for Defense of Democracies analyst Miad Maleki said a comprehensive UAE financial and trade cutoff "may be the most consequential economic action of this war for Iran" [29].

The International Maritime Organization recorded 68 maritime incidents since the war began, with at least 20 seafarers and port workers killed, 35 wounded, and one missing [11]. Lloyd's Market Association described war risk insurance as "on a roller coaster" tracking oil prices and attacks [41]. Oman's foreign minister was due in Iran for further talks on regulating passage through the strait [15], and diplomatic sources described the new sanctions as softer than expected [34].